Chapter 1 Number Recall

Question 1

What are the five rules of surds?

Answer 1

• When multiplying two surds that are exactly the same, the answer is just the number without the root.

root a x root a = a

• When multiplying two surds that are different, the answer is the two different numbers multiplied under one root, in one surd.

root a x root b = root ab

• When dividing one surd by another different surd, the answer is those two numbers as a fraction under one root, as one surd.

root a / root b = root a / b

• a root b x c root d = ac root bd
• a root b / c root d = a / c root b / d

Question 2

What is a surd?

Answer 2

A surd is a root of a rational number.